- added qdarktheme package into the code

libs/qdarktheme/qtpy/qt_compat.py

@@ -0,0 +1,82 @@
+"""Module for Qt compat."""
+from __future__ import annotations
+
+import os
+import sys
+
+
+class QtImportError(ImportError):
+    """Error raise if no bindings could be selected."""
+
+    pass
+
+
+qt_import_error = QtImportError(
+    "Failed to import qt-binding. Check packages(pip list)."
+    "\n\tAvailable Qt-binding packages: PySide6, PyQt6, PyQt5, PySide2."
+)
+
+
+# Qt6
+_QT_API_PYSIDE6 = "PySide6"
+_QT_API_PYQT6 = "PyQt6"
+# Qt5
+_QT_API_PYQT5 = "PyQt5"
+_QT_API_PYSIDE2 = "PySide2"
+
+
+_API_LIST = [_QT_API_PYSIDE6, _QT_API_PYQT6, _QT_API_PYQT5, _QT_API_PYSIDE2]
+
+
+def _get_loaded_api() -> str | None:
+    """Return which API is loaded.
+
+    If this returns anything besides None,
+    importing any other Qt-binding is unsafe.
+    """
+    for api in _API_LIST:
+        if sys.modules.get(f"{api}.QtCore"):
+            return api
+    return None
+
+
+def _get_environ_api() -> str | None:
+    """Return which API is specified in environ."""
+    _qt_api_env = os.environ.get("QT_API")
+    if _qt_api_env is not None:
+        _qt_api_env = _qt_api_env.lower()
+
+    _env_to_module = {
+        "pyside6": _QT_API_PYSIDE6,
+        "pyqt6": _QT_API_PYQT6,
+        "pyqt5": _QT_API_PYQT5,
+        "pyside2": _QT_API_PYSIDE2,
+        None: None,
+    }
+    try:
+        return _env_to_module[_qt_api_env]
+    except KeyError:
+        raise KeyError(
+            "The environment variable QT_API has the unrecognized value "
+            f"{_qt_api_env!r}. "
+            f"Valid values are {[k for k in _env_to_module if k is not None]}"
+        ) from None
+
+
+def _get_installed_api() -> str | None:
+    """Return which API is installed."""
+    # Fix [AttributeError: module 'importlib' has no attribute 'util']
+    # See https://stackoverflow.com/a/39661116/13452582
+    from importlib import util
+
+    for api in _API_LIST:
+        if util.find_spec(api) is not None:
+            return api
+    return None
+
+
+QT_API = _get_loaded_api()
+if QT_API is None:
+    QT_API = _get_environ_api()
+if QT_API is None:
+    QT_API = _get_installed_api()